I would like to ask if it is appropriate to use epsom salt in art activities? 

Epsom Salts are classified as an over-the-counter medication and should not be used for art projects due to regulations. There are some risks to exposure to Epsom Salts, including a drop in blood pressure leading to dizziness and shock. Regulations require that over-the-counter medications may only be in the facility if a physician has prescribed their use for a child. The medication must be labeled for that child and properly stored in a locked cabinet where children cannot gain access.